Field of the Invention
The present invention relates to a display device, and more particularly to a display device in which each pixel is divided into a red subpixel, a green subpixel, a blue subpixel, and a white subpixel.
Discussion of the Related Art
Various flat panel displays, such as a liquid crystal display (LCD), a plasma display panel (PDP), an organic light emitting display (OLED), and an electrophoresis display (EPD), have been developed. The liquid crystal display displays an image by controlling an electric field applied to liquid crystal molecules based on a data voltage. An active matrix liquid crystal display includes a thin film transistor (TFT) in each pixel. The pixels of the liquid crystal display may be divided into red (R) subpixels, green (G) subpixels, blue (B) subpixels, and white (W) subpixels, so as to display various colors and to increase luminance. In the following description, the display device in which the pixels are divided into R, G, B, and W subpixels is referred to as an RGBW type display device.
The liquid crystal display includes, among other things, a liquid crystal display panel, a backlight unit providing light to the liquid crystal display panel, source driver integrated circuits (ICs) for supplying a data voltage to data lines of the liquid crystal display panel, gate driver ICs for supplying a gate pulse (or scan pulse) to gate lines (or scan lines) of the liquid crystal display panel, a control circuit for controlling the source driver ICs and the gate driver ICs, and a light source driving circuit for driving light sources of the backlight unit.
The liquid crystal display is driven through an inversion scheme, which sets polarities of the data voltages charged to adjacent subpixels to be opposite to each other and periodically inverts the polarities of the data voltages, so as to reduce image sticking caused by direct current and to prevent degradation of the liquid crystals. Most of the liquid crystal displays employ a horizontal and vertical 1-dot inversion scheme or a horizontal 1-dot and vertical 2-dot inversion scheme. A 1-dot refers to one subpixel.
A charge amount of subpixels of each color may vary depending on a relationship between data of an input image and a polarity pattern of the pixels. In this instance, a line noise of a longitudinal line shape and color distortion may appear in an image displayed on a pixel array due to the color arrangement of the subpixels.